Abstract: The report presents the design improvement and it's application for brake discs of airplane wheels.Based on the design improvement and several thousands of experiments on more than 10 types of brake disc structures, including the brake for J-x fighter,the shrink and deformation rule of discs are drawn,the causation of deformation is analysed and improvement measures are proposed, A new type of small-piece-linkage brake disc for J-x fighter has been designed. It's service life increases by 8 times over that of the original integrated disc.